Electronic devices sometimes operate in environments that can damage the components and devices. Installation of a device in an automobile, for example, can expose electronic devices to wide swings in temperature as well as fluctuations in power. The power provided by automotive alternators and power regulators may provide power that fluctuates, especially during certain events such as start-up and shut-down of the vehicle. Devices used in manufacturing environments can also experience power fluctuations. If, for example, a power-hungry system or process draws on the manufacturing plant's electrical system, interruptions or fluctuations in power can occur that affect any device connected to the plant's power infrastructure. Electronic devices that can withstand power fluctuations without affecting operation provide benefits in these environments, especially if the electronic device is part of a safety system or other critical system such as an automotive braking system, an automotive transmission system, an automated robotic arm, etc.
Electronic devices may also be subject to electrical overstress (“EOS”) conditions such as an electrostatic discharge (“ESD”) event occurring between exposed pins or terminals of the device. These events can occur if there is a system fault or if the electronic device is exposed to an external charge. For example, the human body can store a charge that can correlate into a stored voltage as high as 25 kV. If a charged body touches an external terminal of the electronic device, that charge can be transferred to and potentially damage the device. Many devices contain ESD protection circuits that provide paths for current due to ESD events to flow without damaging internal circuitry of the device. Providing multiple ESD protection circuits within a device can increase the manufacturing cost of the device.